Potential San Francisco Bay Landslides During El Niño

1996-97 Rainy Season

Debris Flow,
Sierra Nevada
North Fork
of the Stanislaus River
(computer simulation)

This
computer simulation depicts the Sourgrass debris flow (Sierra Nevada, North
Fork of the Stanislaus River), of January 1, 1997. The flow was 2.4 miles
long, with a vertical drop of 2,000 feet. The first half moved 2 to 3 miles
per hour, which is roughly the speed of a fast walk. The second half accelerated
to 12 miles per hour, or the speed of a runner doing a 5 minute mile.

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click for mpeg movie (3.6MB)

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Views of Debris

Close-up view of debris flow, consisting mainly
of fallen trees along part of the lower flowpath.

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Photo courtesy of Jerome V. DeGraff, U.S. Forest Service

Close-up view across the North Fork of the Stanislaus
River, of woody debris remnants of debris flow deposit. Note the people
standing in the center for scale.

Click on photo for a broader-scale, 108kb jpg image (new window) with
no yellow circles